For example, Patent Literature 1 listed below describes one of hybrid electric vehicles including an electric motor, as another power source, other than an engine. In the hybrid electric vehicle disclosed in this Patent Literature 1, when an engine speed target that is a target value of engine speed and an engine torque target that is a target value of engine torque are the coordinates of each of engine operating point targets, interconnecting efficient engine operating point targets in succession to provide target operating line (s) and mapped, and an improvement of fuel efficiency is made by operating the engine at engine speed targets and engine torque targets on the target operating line(s).